After this, any changes to the child task are not saved until the task dependency to the parent task is removed.
Other task dependencies are fine, seems only to be an issue if Parent Task and Task Dependency are the same.
Thinking about it, no point in having a task dependency being the same as the parent, but would hope to have a popup or something saying so.

Removed the option to have a parent as a dependency.. did it via the backend (post-save) since we don't necessarily know which parent is selected on the front end and therefore don't know which tasks to disallow from the dependency box.